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arXiv · 1008.1277

Low-crosstalk bifurcation detectors for coupled flux qubits

P. C. de Groot·A. F. van Loo·J. Lisenfeld·R. N. Schouten·A. Lupascu·C. J. P. M. Harmans·J. E. Mooij
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Abstract

We present experimental results on the crosstalk between two AC-operated dispersive bifurcation detectors, implemented in a circuit for high-fidelity readout of two strongly coupled flux qubits. Both phase-dependent and phase-independent contributions to the crosstalk are analyzed. For proper tuning of the phase the measured crosstalk is 0.1 % and the correlation between the measurement outcomes is less than 0.05 %. These results show that bifurcative readout provides a reliable and generic approach for multi-partite correlation experiments.

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P. C. de Groot, A. F. van Loo, J. Lisenfeld, R. N. Schouten, A. Lupascu, C. J. P. M. Harmans, J. E. Mooij. 2010-08-06. Low-crosstalk bifurcation detectors for coupled flux qubits. https://doi.org/10.1063/1.3367875

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